"use server";

import path from "node:path";
import { safeRevalidate } from "../../lib/safeRevalidate";
import { getPaths } from "yt-dlp-transcript-common/lib/paths";
import { readChannelConfig } from "yt-dlp-transcript-common/controller/channels";
import { preparePlayable } from "yt-dlp-transcript-common/controller/preparePlayable";
import {
  runManagedFunction,
  type StreamActionResult,
} from "yt-dlp-transcript-common/jobs/streamCommand";

// PLAYABLE COPIES AND THEIR TORRENTS (release 21 D3): the `prepare-playable`
// job, as `pnpm ops prepare-playable` posts it (`/api/ops/prepare-playable`).
// The work and its rules are common/controller/preparePlayable.ts.
//
// ONE QUEUE MACHINE-WIDE: a remux reads and writes gigabytes on the archive
// drive, and two channels' worth at once only thrash it.
const PLAYABLE_QUEUE = "playable";

export async function preparePlayableAction(
  slug: string,
  opts: { ids?: string[]; trackers?: string[]; root?: string; dryRun?: boolean },
): Promise<StreamActionResult> {
  const paths = getPaths();
  const channelConfig = await readChannelConfig(paths, slug);
  if (!channelConfig) {
    return { ok: false, error: `Channel "${slug}" not found` };
  }
  if (opts.root !== undefined && !path.isAbsolute(opts.root)) {
    return { ok: false, error: `"root" must be an absolute path` };
  }
  for (const tr of opts.trackers ?? []) {
    if (!/^(wss?|https?|udp):\/\/[^\s]+$/i.test(tr)) {
      return { ok: false, error: `"${tr}" is not a tracker URL (wss://, ws://, https://, http:// or udp://)` };
    }
  }
  return runManagedFunction({
    kind: "prepare-playable",
    queueKey: PLAYABLE_QUEUE,
    paths,
    channelSlug: slug,
    fn: async (onLog, signal, _setProgress, ctx) => {
      const result = await preparePlayable({
        paths,
        slug,
        channelConfig,
        ...(opts.root ? { root: opts.root } : {}),
        ...(opts.ids ? { ids: opts.ids } : {}),
        ...(opts.trackers ? { trackers: opts.trackers } : {}),
        ...(opts.dryRun ? { dryRun: true } : {}),
        onLog,
        signal,
        drainSignal: ctx.drainSignal,
      });
      if (!opts.dryRun && result.prepared.length > 0) {
        safeRevalidate([`/channels/${slug}`]);
      }
      if (result.failed.length > 0 && result.prepared.length === 0) {
        throw new Error(`${result.failed.length} failed, none prepared`);
      }
      if (result.stopped && result.stopped !== "drained" && result.stopped !== "cancelled") {
        throw new Error(`stopped: ${result.stopped}`);
      }
    },
  });
}